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Driver's side heat not working.

1475 Views 11 Replies 4 Participants Last post by  Ranger
OK, I promise, last question fo rtonight.

It started getting a bit cold here in California so I turned on the heater for the first since I bought the car. It blows cold (outside) temp air out of the driver's side, but the passenger's side gets a little warm.

I'd checked the heat when I bought the car a few months ago and it was fine. I've read all the posts on this site. I can see the passenger side acctuator moving (behind the little panel in the glovebox). I can't find the driver's side acctuator.

When I put the heater to defrost for the windshield hot air blows out of the passenger's side of the vent on top of the dash, but nothing on the driver's.

I should note that when I pulled codes it showed B1340 (Air Mix Door One Movement Fault) and B1341 (Air Mix Door Two Movement Fault). What do they indicate exactly and when should I go looking for the problem.

Also, I saw a post about a guy who's heater core became clogged by BarsLeak Gold. I recently had my radiator flushed and I add the Bars Leak Gold Label powder based on recommendations from this site. Should I flush the heater core? If so, how?

Are there other things I should be checking.
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I agree with Turbojimmy. Don't mess with the core. On my '97 Deville I think the driver side acutator was below the passengers and was accessable from under the dash (remove the hush panel). Try running the temp up to max, then back down to excersise a possible sticking door or actuator. That used to work for me. Otherwise, look for a vacuum leak before replacing the acuator.
daddydg said:
Why is changing the HVAC programmer so horrible?
Because it is big $$$$.

Flush the heater core. I think that may solve your problem.
Still don't know what year car or what engine your talking about but in either case, locate the two heater hoses going through the firewall at the passenger side. Remove both, hook a garden hose to one and turn it on. Water will flush through it and out the other hose. Then reverse it by putting the garden hose on the other one.
Add it to your profile and it will always be there.
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